Rail transportation is developing rapidly in China. High-speed railway and inter-city railway as well as light rail and subway are all under rapid construction. However, with the construction and operation of rail transportation facilities, more and more engineering problems appear. Dynamic stability of the subgrade under train load affects safe operation of the train; vibration of the rail and the subgrade created by interaction between wheels and rail also significantly affects the environment and human's daily life. With the increasing train speed of high-speed railway, interaction between the train and the rail becomes more severe. When the speed of the train reaches a critical wave velocity of the soil, Mach effect will appear, which seriously threatens the safe operation of the train. The train load is transmitted to the structure under the rail via interaction between the wheel axle and the rail. Compared with conventional fixed-point cyclic loading, the interaction between the wheel axle and the rail typically has moving effect and speed effect. As the train moves, each structure layer under the rail experiences a same loading procedure along the moving direction of the train. This loading characteristic is quite different from the fixed-point loading, which results in that the rail structure and the subgrade structure represent different dynamic performance. Therefore, achieving an effective simulation of load moving process of the whole train is significant to the research in actual dynamic performance of the rail transportation infrastructure.